116 cases of early ductal breast cancer diagnosed during 1971 to 1981 were analysed. In 65 cases no invasion was detectable. 37 cases showed an early stromal invasion and in 14 cases the invasion was questionable. A palpable mass was seen in 32% of the noninvasive and in 46% of the early invasive cases. The most important mammographic signs were grouped, suspicious microcalcifications (87%). Multicentricity occurred in 26% of the noninvasive and 43% of the early invasive cases. Two cases of the noninvasive and two of the early invasive group had axillary metastasis. Positive nodes were seldom in early ductal carcinoma (3%) compared to 42 invasive comedo-carcinomas (36% positive axillary nodes). In the follow-up five local recurrences were detected in the noninvasive group and one each in the other groups. In the noninvasive group 17% local recurrences occurred after breast conserving modalities compared to 4% in mastectomy patients. As no reliable data for the selection and the results of breast preserving modalities are available now, mastectomy and axillary dissection may be the safest therapy. Only in small intraductal breast cancer (under 25 mm) the breast may be conserved (wide excision, segmental resection, quadrantectomy), if complete excision is carefully controlled by mammography and histology and follow-up is guaranteed.